On Sun, Jan 28, 2007 at 12:47:18PM -0500, Thor Lancelot Simon wrote: > > Wouldn't the old root also (until it actually expires) verify any > > certificates signed by the new root? If so, why does a server need to > > send the new root? So long as the recipient has either the new or the > > old root, the chain will be valid. > > That doesn't make sense to me -- the end-of-chain (server or client) > certificate won't be signed by _both_ the old and new root, I wouldn't > think (does x.509 even make this possible)? > > Or do I misunderstand?
The key extra information is that old and new roots share the same issuer and subject DNs and public key, only the start/expiration dates differ, so in the overlap when both are valid, they are interchangeable, both verify the same (singly-signed) certs. What I don't understand is how the old (finally expired) root helps to validate the new unexpired root, when a verifier has the old root and the server presents the new root in its trust chain. -- /"\ ASCII RIBBON NOTICE: If received in error, \ / CAMPAIGN Victor Duchovni please destroy and notify X AGAINST IT Security, sender. Sender does not waive / \ HTML MAIL Morgan Stanley confidentiality or privilege, and use is prohibited. --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]